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WASHINGTON — President Donald Trump's strengths as a politician include his ability to mercilessly attack his opponents, his devoted base of support, and his political branding and showmanship. But they don't include what his job will be over the next two days — his role as comforter-in-chief to devastated Puerto Rico and a Las Vegas that witnessed the deadliest mass shooting in American history.

In Trump's eight months as president, we've seen him react to tragedy to with varying degrees of success — the shooting of House Majority Whip Steve Scalise (A+), visiting Texas and Florida after their hurricanes (B or a C), and responding to the violence in Charlottesville, Va. (F). But today's and tomorrow's consoler-in-chief jobs might be his toughest yet.

In Puerto Rico, he's stepping into a place where his administration's handling of the hurricane-relief efforts has been criticized, and where he's already attacked San Juan's mayor. "Such poor leadership ability by the Mayor of San Juan, and others in Puerto Rico, who are not able to get their workers to help," he tweeted on Saturday. "They want everything to be done for them when it should be a community effort. 10,000 Federal workers now on Island doing a fantastic job."

And in Las Vegas, he'll be responding to an act — gun violence — that has never been one of his chief political concerns in a state — Nevada — that he lost to Hillary Clinton in the 2016 general election.

I won't back down (on terrorism) vs. Don't come around here no more (on gun violence)

Responding to the mass shooting in Las Vegas, White House Press Secretary Sarah Huckabee Sanders said that yesterday wasn't the time to discuss gun violence. "I think today is more … a day of reflection, a day of mourning, a day of gratefulness for those that were saved. And I think that there will be, certainly, time for that policy discussion to take place, but that's not the place that we're in at this moment."

But contrast that response — as well as Trump's sole tweet on the mass killing ("My warmest condolences and sympathies to the victims and families of the terrible Las Vegas shooting. God bless you!" — with how Trump has IMMEDIATELY responded to terrorism committed in the name of Islam.

After the December 2015 shooting in San Bernardino, Trump proposed his Muslim ban. "Until we are able to determine and understand this problem and the dangerous threat it poses, our country cannot be the victims of horrendous attacks by people that believe only in Jihad, and have no sense of reason or respect for human life," he said.

After the June 2016 violence in Orlando, he tweeted, "Appreciate the congrats for being right on radical Islamic terrorism, I don't want congrats, I want toughness & vigilance. We must be smart!"

And after the June 2017 terrorist attack in London, Trump said, "At least 7 dead and 48 wounded in terror attack and Mayor of London says there is 'no reason to be alarmed!'"

Breakdown — on Nevada's gun debate

NBC's Benjy Sarlin: "Sunday's massacre in Las Vegas — the worst mass shooting in modern U.S. history — shone a light on Nevada's close partisan divide that has for years made it a national flash point in the battle over gun rights. Both sides have poured millions of dollars into campaigns to restrict or loosen gun laws, efforts that have been spurred by high-profile shootings both in Nevada and around the country."

"Overall, the state's restrictions are relatively light. There are no permit requirements for purchasing handguns, rifles and shotguns, according to the National Rifle Association. Residents are allowed to carry guns openly throughout the state, a provision that attracted scrutiny when self-styled militia groups gathered in 2014 to support rancher Cliven Bundy's standoff with authorities. 'There is very little on the books,' said Robyn Thomas, executive director of the Law Center to Prevent Gun Violence, a gun safety group."

Running down a dream: Democrats pursue gun control

Meanwhile, NBC's Jonathan Allen looks at how the Democratic Party's long roster of possible 2020 candidates all called for gun control after the Las Vegas shooting.

"Not long ago, Democratic presidential hopefuls shied away from talking about gun control — or at least made sure to pepper their rhetoric with nods to the Second Amendment. Not anymore," Allen writes.

"'We cannot simply throw up our hands or continue to justify the presence of weapons of war whose primary purpose is to kill the largest number of human beings in the shortest amount of time possible,' freshman Sen. Kamala Harris, D-Calif., said in a statement."

"Sen. Elizabeth Warren, D-Mass., who has urged fellow Democrats to advocate for gun control, tweeted that it's time for a national conversation about guns."

"And Vermont Sen. Bernie Sanders, who was hammered for sometimes voting with the gun lobby by Hillary Clinton in the 2016 Democratic presidential primary, said Americans should do 'everything we can' to stop gun violence."

Free fallin' prospects to pass tax reform?

On "Meet the Press" this past weekend, retiring Sen. Bob Corker, R-Tenn., gave this warning on tax reform: "[I]f it looks like to me, Chuck, we're adding one penny to the deficit, I am not going to be for it, okay?"

And yesterday, Sen. Rand Paul, R-Ky., tweeted, "This is a GOP tax plan? Possibly 30% of middle class gets a tax hike? I hope the final details are better than this."

Remember, if tax reform turns into a party-line vote in the Senate, Republicans can't afford more than two defections, and already you're seeing Senate GOP opposition on the cost (Corker's concern) and the possibility of a tax increase on the middle class (Paul's concern).

Into the great wide open (of an inspector general investigation)

"The inspector general for the Interior Department has opened an investigation into Secretary Ryan Zinke's travel during seven months in office, from his use of taxpayer-funded charter and military planes to his mixing of official trips with political appearances," the Washington Post writes.

"Nancy K. DiPaolo, a spokesperson for Deputy Inspector General Mary Kendall, described a broad investigation into Zinke's 'travel in general,' including "modes of travel, costs and schedules.'"

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